Defensive publication



DEFENSIVE PUBLICATION UNITED STATES PATENT OFFICE Published at therequest of the applicant or owner in accordance with the Notice of Apr.11, 1968, 849 0.G. 1221. Identification is by serial number of theapplication and the heading indicates the number of pages 01!specification, including claims, and of sheets of. drawing contained inthe application as originally filed. The file of this application isavailable to the public for inspection; reproduction may be purchasedfor 30 cents per sheet.

Applications published under the Defensive Publication Program have notbeen examined as to the merits of alleged invention. The Patent Oflicemakes no assertion as to the novelty of the disclosed subject matter.

PUBLISHED SEPTEMBER 16, 1969 657,707 CRYSTALLINE POLYSTYRENE GRAFTCOPOLY- MERS AND THEIR PREPARATION Donald J. Shields, P.O. Box 511,Kingsport, Tenn. 37662; James E. Guillet, 31 Lagebrush Lane, Don Mills,Ontario, Canada; and Harry W. Coover, Jr., P.0. Box 511, Kingsport,Tenn. 37662 Continuation of application Ser. No. 530,352, Feb. 28, 1966,which is a continuation-in-part of application Ser. No. 791,531, Feb. 6,1959. This application Aug. 1, 1967. Published Sept. 16, 1969 Int. Cl.C08f 19/04 N42 US. Cl. 260-878 No Drawing. 10 Pages SpecificationCrystallizable, homogeneous graft copolymers of styrene are produced bycontacting styrene with a catalytic mixture containing trialkyl aluminumwherein the alkyl groups are of 1 to 12 carbon atoms and vanadiumtrihalide, prior to any substantial reaction between said trialkylaluminum and said vanadium trihalide, to form a reaction mixturecontaining a living, solid polystyrene onto which a-monoolefinichydrocarbons of up to 10 carbon atoms may be polymerized to form a graftcopolymer. Polymerization of the styrene in the initial step can beconducted in the presence or absence of an inert diluent at atemperature of 0250 C., preferably 60-250 C. and a pressure in a rangeof 0-1000 p.s.i.g. or greater, preferably 300-1000 p.s.i.g. The reactiontime is ordinarily within the range of 0.5 to 5 hours. The preferredcatalyst is a mixture of triethyl aluminum and vanadium trichloride. Thegraft copolymerization reaction can be carried out at temperaturessimilar to those employed for the pre-polymerization of the styrene. Thepreferred a-olefinic hydrocarbons graft-copolymerized onto thepolystyrene are ethylene and propylene.

